KINSHASA, Jan 12 (Reuters) - Republican Guard soldiers and police officers surrounded the residence of the runner-up in Democratic Republic of Congo's presidential election on Saturday before he could leave to file a fraud complaint in court, witnesses said.

Dozens of supporters of Martin Fayulu, who had gathered outside his Kinshasa hotel and residence and were chanting slogansd against outgoing President Joseph Kabila and President-elect Felix Tshisekedi, fled inside the building when the security forces arrived, a Reuters witness said. (Reporting By Stanis Bujakera Writing by Aaron Ross Editing by Mark Heinrich)